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encapsulated crawl space

Crawl Space Vapor Barrier Installation

Vapor barriers are essential in sealing your crawl space and isolating it from the earth. There are many options when it comes to vapor barriers. Learn which ones will benefit your crawl space, and what to stay away from.

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The crawl space holds the most crucial parts of the home. From your plumbing to your HVAC system to your electrical wiring, this tiny space contains nearly everything your home needs to run efficiently.  

If any moisture seeps through to this all-too-important area, your entire house can face terrible consequences. 

Installing vapor barriers is a good first step. However, not all vapor barriers are made the same. You need a thick barrier capable of withstanding even the rowdiest storms. What kind of damage can your home face without the proper moisture protection methods?  

How Will I Know My Crawl Space Needs Repairs?  

There are very specific signs you can look out for to ensure minimal damage and simple repairs. What are some crawl space problem signs you should watch out for?  

  • Leaks and Flooding  

Because your plumbing is located within the crawl space, spotting a leak within your home should concern you. Even a small leak might indicate larger issues hidden behind your walls. It is possible that your crawl space is already flooded and any leaks you find are coming from that standing water finding ways to seep out to your home.  

Placing a bucket under any leak you find is not a solution. If you do not fix leaks in time, they will very likely grow larger without you noticing. This can be devastating during any huge storm or snowfall. Without the proper moisture protection, you will easily find your crawl space entirely flooded, and any belongings you stored down there ruined along with it.  

The pressure from all that water flowing in could potentially lead to your walls cracking as well. These cracks can disrupt fundamental components that support your home—namely your foundation.  

  • Musty Smell  

An odd stench wafting around your first floor should not simply be waved away. It may be a sign that you have standing water or even sewage washed up inside your crawl space. The longer that water lingers, the worse the smell will become. Standing water can also attract other issues to your crawl space that you do not want to deal with, namely pests and mold growth.  

  • Pests  

A musty smell can also indicate that your crawl space has a severe pest problem. Pests, such as cockroaches, are drawn to humid areas or places with plenty of moisture. They will then emit a musty odor to attract other cockroaches nearby. The smell may become especially prominent when you have a serious infestation on your hands. You may even see these little creatures scuttling across your floor now and then.  

Other pests, such as silverfish, centipedes, and even earwigs will all be drawn to a home that has moisture issues. No homeowner wants to deal with even one of these insects, let alone an entire infestation of them. This is one of many reasons why it is essential for homeowners to properly encapsulate their crawl spaces from moisture to lessen pests’ interest in this space. 

  • Mold, Mildew, or Fungi  

Moisture in your crawl space can entice mold, mildew, or fungi to grow within. Though mold is not particularly toxic, it does present a serious health hazard for homeowners with asthma or chronic lung diseases.  

A single black spot of mold you see consists of millions upon millions of mold spores that will spread to other rooms in your home. Mold growth within the crawl space can be especially dangerous because of your HVAC system. This system could circulate mold spores around your home, which may then adversely affect your health and the health of your family.  

What Causes Issues Within Crawl Spaces?  

If the crawl space is so out of the way that even the average homeowner cannot access it, how does anything else creep in and cause trouble within it? As it turns out, it is very easy for moisture to infiltrate this space.  

Moisture is one of the most common causes of water damage and destruction within your crawl space. How moisture trickles through in the first place, however, can vary from home to home. What are some common causes of issues you find in crawl spaces? 

  • Humidity  

Humidity is essentially moisture that floats in the air. Of course, with most foundations and outer walls being made up of concrete, humidity might not seem like a big deal. Unfortunately, humidity can easily seep through the pores of your foundation and infiltrate your crawl space that way.  

It will not help that your crawl space is covered in thick insulation that already propagates warm air throughout this small space. Couple this with any humidity that seeps through, and you have a recipe for disaster.  

The relative humidity in the air is measured through the percentage of water vapor the surrounding air can hold. If the relative humidity in your crawl space is already at 100 percent capacity, then any humidity that enters after will begin to condense into liquid water droplets and flood your crawl space. Humid climates are especially vulnerable to this kind of damage.  

Humidity on its own can also ruin electrical wiring or other delicate systems you have stored in your crawl space. This space must remain as dry as possible to prevent this damage from occurring. That is why having an effective vapor barrier is crucial. 

  • Hydrostatic Pressure  

Rainwater, melted snow, and humidity can all collect within the soil surrounding your foundation. The more moisture your soil takes on, the more pressure this combination exerts on your foundation. Eventually, your foundation will either shift or crack, allowing water to flood your crawl space. This phenomenon is known as hydrostatic pressure.  

Hydrostatic pressure can also take the form of moisture seeping into your concrete foundation’s pores and freezing in the winter. The expanding ice will then fracture your foundation from within and allow moisture to seep into your crawl space more easily.  

  • Settling Foundation  

The foundation of your home often lies within your crawl space. Anything that negatively affects your foundation will in turn affect your crawl space as well. 

Your home’s foundation rests above a plot of compact soil. During heavy storms or other severe weather, it is very likely for some of that soil to wash away and leave voids for the water to fill. Once that water drains away, your foundation loses the support it once had. It will settle into the remaining soil and collapse or crack. 

  • Ineffective Vapor Barriers 

A vapor barrier is meant to protect your crawl space from any moisture that tries to seep through. It’s possible your crawl space already had a vapor barrier installed, but it proved ineffective in some way. Your old vapor barrier might have been too thin and torn apart as a result. If you notice your home still has high levels of indoor humidity, then this could also mean your current vapor barrier isn’t doing its job. 

This is why you need an expert to inspect your crawl space every year. They can recommend a 20-mil vapor barrier that is far less likely to tear or puncture, no matter the weather conditions. A thicker vapor barrier can also protect your crawl space from gathering any moisture or humidity. You won’t have to worry about any moisture problems or mold within this space ever again with the proper barrier installed! Plus, pests will be less interested in your crawl space once its moisture problems have been addressed. 

Wet insulation in a home

Dealing with Ineffective Crawl Space Vapor Barriers 

Determining what kind of vapor barrier suits your crawl space best can be a challenge, especially if you’re not entirely sure what kinds of vapor barriers local contractors can make available to you. At the end of the day, however, lean on your common sense. Lower-density vapor barriers, for example, aren’t going to hold up as well in a home that sees a significant amount of seepage. Comparatively, vapor barriers that are too dense may lower the overall humidity of your crawl space to a point where your home’s no longer as healthy as it once was. There may even be times when the vapor barrier you have installed doesn’t fit your crawl space. 

If you want to avoid working with ineffective vapor barriers, you can. Be sure to talk through every detail of your installation with the professional contractors serving your area. You can even take your crawl space’s measurements prior to your installation so that professionals can compare their numbers against yourself. Above all else, though, do not install a crawl space vapor barrier in a space that hasn’t actively been repaired. Vapor barriers are tough, but even they can’t stand up for long against a crawl space that’s taking on a significant amount of water. Instead, make sure that your crawl space is in good condition when you first have your vapor barrier installed. This way, you can rest assured knowing that your barrier should last a good long while, no matter what conditions outside of your home look like. 

Vapor Barrier


Why Is the Crawl Space Important?  

A stable, waterproof crawl space is crucial to the health of your home. This is because it contains very important systems within it, namely your:  

  • HVAC system  
  • Insulation  
  • Electrical wiring  
  • Plumbing  
  • Air ducts  
  • Foundation

Where is the Crawl Space Located? 

The crawl space is typically located between your ground and first floor. Essentially, it elevates your home off the ground as well as houses all your home’s important components. This is why you will typically notice crawl space problems even in your first floor.  

The crawl space is typically very narrow and humid, and you might not be able to maneuver all that well down there. There is also the possibility that you might hit an important system or get stuck or lost. This is why you should leave any repairs you might need to the experts at JES Foundation Repair instead.  

How Big Is the Crawl Space?  

As the name implies, a crawl space is just big enough for an adult to crawl around in. This space is usually built as an alternative to a full basement, though your home can easily have both. The ceiling of this space can range anywhere from one to three feet high. However, even crawl spaces with higher ceilings can be unsafe for the average homeowner.  

This is because of all the various systems embedded in this space. Navigation can be narrow and tricky. It is best to leave any repairs you need to the crawl space experts at JES Foundation Repair. We are used to working in tight spaces without disrupting any crucial components, so you can rest easy while reaping the benefits.  

The encapsulation process ultimately helps keep any moisture out of your crawl space and home as a whole. However, if you do not have a vapor barrier strong enough to protect these spaces from moisture (if you have one at all), then you will find your home and even your family facing all sorts of issues.  

The most harmful damage a poorly encapsulated crawl space can cause is putting you and your family at risk of becoming ill. How exactly does an unattended crawl space contribute to health issues?  

Mold and Mildew Health Issues  

Sitting moisture can encourage all sorts of unhealthy fungi to grow within your home. Mold and mildew are both types of fungi that, while not necessarily toxic, can present plenty of health issues if left to fester in dark spaces. Both fungi will grow anywhere with plenty of moisture, including within your crawl space.  

This can be dangerous for several reasons. For one, they both spread very, very easily and can grow on almost any organic material. Should their spores get into your HVAC system or even your plumbing, you can expect to see mold or mildew growing in other parts of your home and infecting you that way.  

Mold and mildew can adversely affect even those that aren’t sensitive or allergic to it. The CDC states that the average healthy person will likely suffer from a stuffy nose, red or itchy eyes or skin, coughing, and wheezing. However, those with asthma or immunosuppression are likely to have their lungs infected with the mold or mildew itself, among other intense reactions.  

Health Hazards of Pest Infestations  

Pests are ridden with all sorts of diseases, and those attracted to flooded homes are no different. Cockroaches, mosquitos, and other similar insects tend to carry such diseases as Lyme disease, strep throat, Rocky Mountain spotted fever, salmonella, malaria, and much more. Even if the pests that invade your home do not happen to carry diseases, their shed skins alone can trigger allergic reactions in both sensitive and healthy people alike.  

Dealing with severe illness on top of an infestation and constantly flooded crawl space will only worsen your condition further. It is best to encapsulate your crawl space before your home reaches this point. When you encapsulate your crawl space you are reducing moisture in this space, which reduces pests’ interest in the space as well. 

Contact JES Foundation Repair for Free Crawl Space Inspections in Virginia, Maryland, and D.C.  

A safe and healthy home begins with a dry crawl space. The crawl space experts at JES Foundation Repair can inspect your crawl space for any issues at no cost to you. We can also offer you a free quote on our quality crawl space encapsulation services, which includes the installation of the CrawlSeal™ vapor barrier.  

Contact us to schedule your free crawl space inspection today

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